摘要
由于光学衍射效应,常规光学显微技术的分辨率无法满足100 nm以下形状和结构特征检测的需求。为了在二维单分子层石墨烯检测中用光学显微,弥补非光学检测技术如扫描隧道显微镜(STM)和原子力显微镜(AFM)等固有的过小的视场、过长的检测时间和过高的费用等诸多不足之处,报道了一种新的宽场偏振参数模式化非直观超显微成像(PIMI)方法。该方法通过在传统光学显微光路中增设偏振模式化装置,精确地调制入射光波的偏振状态,利用光波与物质的耦合作用变化和携带近场物质结构信息的远场光场变化,通过分析不同偏振条件下所得图像变化,反演计算得到近场光波参数图像和物质结构特征,实现对物质结构和形貌的50 nm级光学超分辨。利用该方法,通过针对石墨烯而开展的一系列对比验证实验,初步实现了对其颗粒边界、层厚、褶皱的分辨,在二维平面内实现了光学超显微分辨。
Due to optical diffraction, the resolution of conventional optical microscope cannot meet the need of sub-100 nm shape and structural detection and analysis. In order to use optical microscopy in two dimensional monolayer graphene imaging, and make compensation for the inherent disadvantages of non-optical imaging techniques such as scanning tunneling microscopy (STM) and atomic force microscopy (AFM), narrow image field, long detection time, excessive cost and many other adverse factors. A new microscopic imaging technique, the polarization parameter indirect microscopic imaging (PIMI) technique is reported. PIMI, by adding polarization modulation module in the light path of a conventional optical microcopy, accurately adjusting the polarization state of the incident light, bring near-field light and matter coupling results to the far-field as intensity variation, retrieves near field polarization status distribution map from the far-field variation curve to form indirect images for analyzing microscopic structures to the resolution of 50 nm scale. By using the proposed PIMI system, a series of comparison validation experiments focused on graphene are carried out to analyze its grain boundaries, layer numbers, wrinkles, and achieve optical super-resolution in the two-dimensional plane.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2014年第B12期183-189,共7页
Acta Optica Sinica
基金
国家自然科学基金(61275163)
关键词
成像系统
非直观成像
超显微
偏振参数
衍射极限
石墨烯层厚
imaging systems
indirect imaging
super-resolution microscopy
polarization parameters
diffraction limit
thickness of graphene